直流微电网多源并联自主均流控制策略Autonomous Current Sharing Control Strategy for Parallel Micro-sources in DC Microgrids
张勤进;庄绪州;刘彦呈;王川;
摘要(Abstract):
实现微源间负荷电流的精确分配及母线电压的无差调节是直流微电网重要的控制目标,但由于线路阻抗及低速通信的存在,传统下垂控制很难同时满足均流及稳定性的要求。提出一种基于低频低幅值交流信号注入的多源并联自主均流控制策略,在各变流器直流输出上注入交流小信号,并使其频率与输出直流电流产生频率–电流下垂特性,利用产生的无功功率环流调节各变流器输出直流电压,进而在反馈机制下,实现多变流器间的并联控制及负荷电流的精确分配;在此基础上,利用限幅及负阻抗环节,提出一种改进的母线电压补偿方法,进一步降低了由于线路阻抗造成的电压跌落,该方法无需互联通信线,无需改变硬件结构,易于实现;最后利用小信号建模,分析了控制策略的稳定性和动态性能。仿真和实验验证了所提方法的可行性和有效性。
关键词(KeyWords): 直流微电网;均流控制;注入交流电压;母线电压调节;虚拟负阻抗
基金项目(Foundation): 国家自然科学基金(51709028,51979021);; 辽宁省自然科学基金项目(20170540082);; 中央高校基本科研业务费专项资金(3132018262)~~
作者(Author): 张勤进;庄绪州;刘彦呈;王川;
Email:
DOI: 10.13335/j.1000-3673.pst.2019.1664
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